Remotely operated air brake bleeding apparatus

ABSTRACT

A remotely operated bleeding device for use with air brake systems provided on trains, and particularly for use with freight cars. the device comprises an air cylinder connected to the main brake air pressure pipe. The cylinder has a piston and piston rod, and a helical compression spring arranged to bias the piston toward the end of the cylinder at which air pressure is introduced. The spring and piston arrangement is such that application of air pressure to the air cylinder greater than about 20 psi compresses the spring and forces the piston to remain at the opposite side of the cylinder. The piston remains so during normal operation of the train and braking system. The piston rod is provided with a latch bar either connected thereto or intgral therewith, and a latch bar engaging member cooperating therewith, and operatively connected to the bleeder valve of the car. The slow release of air pressure causes the latch bar to engage the operating member and to bleed the brake cylinder. Means is provided for disabling the bleeder device when emergency braking is applied to the cars, or when the brake air line is broken as the result of an accident.

Sill United States Patent [191 14s] Aug. 14, 1913 REMOTELY OPERATED AIRBRAKE BLEEDING APPARATUS [76] Inventor: Clark D. Sill, 217 N. Grand,

Marshall, Mich. 49068 [22] Filed: July 3, 1972 [21] Appl. No.5 268,499

McClure et al 303/68 Primary Examiner-Duane A. Reger A tmmey Roy A.Plant and Samuel Kurlandsky [57] ABSTRACT A remotely operated bleedingdevice for use with air brake systems provided on trains, andparticularly for use with freight cars. the device comprises an aircylinder connected to the main brake air pressure pipe. The cylinder hasa piston and piston rod, and a helical compression spring arranged tobias the piston toward the end of the cylinder at which air pressure isintroduced. The spring and piston arrangement is such that applicationof air pressure to the air cylinder greater than about 20 psi compressesthe spring and forces the piston to remain at the opposite side of thecylinder. The piston remains so during normal operation of the train andbraking system. The piston rod is provided with a latch bar eitherconnected thereto or intgral therewith, and a latch bar engaging membercooperating therewith, and operatively connected to the bleeder valve ofthe car. The slow release of air pressure causes the latch bar to engagethe operating member and to bleed the brake cylinder. Meansis providedfor disabling the bleeder device when emergency braking is applied tothe cars, or when the brake air line is broken as the result of anaccident.

9 Claims, 7 Drawing Figures 1 1 REMOTELY OPERATED AIR BRAKE BLEEDINGAPPARATUS BACKGROUND OF THE INVENTION Still further objects andadvantages of the invention will appear as the description proceeds.

To the accomplishment of the foregoing and related ends, the invention,then, consists of a remote bleeding apparatus for use with railroad airbrakes, herein fully described and particularly pointed out in theclaims, the annexed drawings, and the: following description settingforth in detail certain illustrative embodiments of the invention, suchdisclosed embodiments illustrating, however,'but several of the variousways in which the principle of the invention may be used.

trains have an air operated brake cylinder on each car which operatesthe brakes. An air reservoir isalso provided on each car communicatingwith the brake cylinder through a car brake control valve. The controlvalve is connected to the main brake air line or pipe in which airpressure is maintained at a value of 75-80 psi during normal operation.When the brakes pf each car are to be applied, the engineer operates avalve which temporarily reduces the air pressure in thev entire line byan amount of from 7 to 25 psi. When braking action is discontinued, thepressure within the air line rises again to a value of 75-80psi. In caseof emergency the brake control can be opened so that the air pressure isreduced to psi (in excess of atmospheric pressure), thereby applyingfull brakes. Moreover, if an accident should occur and the brake linebetween any two cars broken, the reduction of pressure to atmosphericcauses an immediate full application of the brakes in every car.

When a train comprising a plurality of freight cars reaches amarshalling or classification yard, the cars are disconnected and theindividual cars or groups of cars switched to various sidings. However,when a group of freight cars is disconnected from the main train or fromthe locomotive, the air line is opened, thereby setting the brakes ofeach car to full emergency condition. As a result, the cars cannot bemoved until the air in the brake operating cylinders is bled off. Thisis provided by a bleeding valve mounted on each car and connected withthe braking system, and arranged to be hand-actuated by means of alever. This can be extremely time consuming and expensive when a largenumber of cars must be individually bled. It has been estimated that aperiod of thirty minutes is required for one brakeman to bleed sixtycars.

SUMMARY OF THE INVENTION Accordingly, it is an object of the presentinvention to provide an apparatus for remote bleeding of the brakecylinders of each car.

It is a further object to provide an apparatus of the type describedwith which bleeding of the brake cylinders of all the cars may beaccomplished by controls lo- BRIEF DESCRIPTION OF THE DRAWINGS In theannexed drawings:

FIG. 1 is a side elevational view of the apparatus of the invention,diagrammatically illustrating the interconnection of some of thecomponents.

FIG. 2 is a view of the apparatus of FIG. 1 taken at the line 2--2 ofFIG. 1, looking :in the directionof the DESCRIPTION OF THE SPECIFICEMBODIMENTS Referring more particularly to FIG. 1, the remote bleedingapparatus 10, according to the invention, is shown comprising an aircylinder 11 having a piston 12 slidably mounted therein and a piston rod13 affixed to the piston 12. A helical compression spring 14 is mountedover the piston rod 13 and urges the piston 12 toward the end of thepiston having a compressed air inlet (retracted position). Compressedair is supplied from the main brake pipe 15 which runs throughout thelength of the train, by means of a. connecting pipe 16.

A latch bar 17 is connected to the remote end of the piston rod 13. Thelatch bar 17 may be integral with the piston rod 13, affixed thereto asby welding or bolts, or alternatively hingedly or pivotally coupledthereto and independently supported. The latch bar 17 is provided with alatch notch 18-having an inclined ramp 19 at one side and a hook 20 atthe other. A bar ramp 21 is provided at the end of the latch bar 17connected to the piston rod 13. A latch bar engaging rod .25 iscooperatively arranged with the latch bar 17 and comprises a connectingrod 26 pivotally connected to the main bleeder control rod 27 of thefreight car. The rod 27 is connected to the bleeder valve arm 28 of thebleeder valve 29.

The upper portion of the latch bar engaging rod 25 has bifurcatedmembers 30 connected at their ends by a transverse notch engaging member31.

In operation, air pressure in the amount of -80 psi is applied to themain brake pipe 15. Compressed air is consequently supplied through theconnecting pipe 16 and into the chamber of the cylinder 11. Thecompression spring 14 and piston diameter are so designed that thespring biasing force can be overcome by an air pressure of at least 20pounds applied to the chamber of the cylinder 11. Consequently, thepiston is pushed forward to its farthermost position, as shown inFIG. 1. In this position the notch engaging member 31 lies on or belowthe ramp 21. The apparatus remains in this position through normaloperation of the train, including normal braking operation, since duringsuch normal operation and normal braking operation the air pressure inthe main brake pipe remains sufficiently high to retain the spring 14 incompressed condition.

When a train has arrived at the marshalling yard and it is desired todisconnect a group of freight cars in order to reclassify the cars bymoving them into the proper sidings, the braking system is applied tostop the train. At this point the bleeding apparatus is still in theposition shown in FIG. 1. The engineer then slowly moves the brakecontrol to decrease the air pressure still further. When the pressurereaches a value below pounds, the spring 14 retracts the piston 12toward the other end of the cylinder 11. As the latch bar is slowlymoved by the piston, the transverse engaging member 31 drops into thenotch 18 where it is retained by the hook 20. The latch bar then drawsthe bleeder operating rod with it, thereby moving the main bleedercontrol rod 27 and causing the air to be bled from all the brakes. Nowwhen the cars are disconnected, the brakes will not be set, and the carscan be freely moved about. When the cars are recoupled to the train andthe brake air pipes reconnected, the air pressure in the lines of eachcar is reestablished at 75-80 psi. Consequently, the piston rod 13 isextended, causing the transverse notch engaging member 31 to ride up theramp 19 and become disengaged from the notch 18 and hook 20 and toassume the normal position shown in FIG. 1.

When the train is traveling and the bleeding apparatus is in the normaloperating condition shown in FIG. 1, should it become necessary to applythe brakes in full emergency service by causing the pressure in the mainbrake pipe 15 to be reduced substantially to atmospheric pressure, thespring 14 causes the piston 12 to retract rapidly to the other end ofthe cylinder. This causes the notch engaging member 31 to ride rapidlyup the bar ramp 21 and to acquire an upward momentum. When the notchengaging member 31 descends, it will have cleared the notch 18 and hook20 and will land on the upper edge of the latch bar beyond the notch 18,as shown in FIG. 3, thus disabling the bleeding apparatus. Thus, thebleeding apparatus does not interfere with emergency braking. The sameis true in the case of an accident in which the main brake pipe 16 isdisconnected at any point. As a result there is a rapid decrease in airpressure to atmospheric pressure, causing rapid movement of the piston12 and latch bar 17, so that the notch engaging member 31 again rides upthe ramp 21 and clears the notch 18 and is not engaged by the hook 20.The brakes in every car are consequently set to full emergency brakingcondition.

Referring to FIGS. 5-7, another embodiment of the invention is shown inwhich the bleeding apparatus 35 comprises a primary air cylinder 36 anda secondary air cylinder 37. The primary air cylinder 36 is mounted on abracket 38 and includes a piston 39 affixed to a piston rod 40 andhaving a latch bar 41 connected to the remote end of the piston rod 40.The latch bar 41 may be integral with the piston rod 40, afiixedthereto, or pivotally connected thereto. The latch bar 41 is providedwith a notch or detent 42 having a bearing surface 43 on one side and abearing surface 44 on the other. A helical compression spring 45 ismounted over the piston rod 40 and biases the piston 39 toward the fullyretracted position. The spring should be so designed that it can beovercome and fully compressed when an air pressure of about twentypounds is present in the main brake line, and additionally should besufficiently strong that it can operate the bleeder apparatus.

The secondary air cylinder 37 is also supported by the bracket 38 andcomprises a piston 47 having a piston rod 48. A helical compressionspring 49 is mounted over the piston rod 48 biasing the piston 47 towardfully retracted position. The secondary cylinder should be so designedthat the spring 49 is fully compressed when there is an air pressure ofabout 20 psi in the main brake line, but the spring need not be asstrong as the spring 45, since the spring 49 does not operate thebleeder valve directly. An override bar 50 is connected to the outer endof the piston rod. The override bar 50 may be integral with the pistonrod, affixed thereto, or pivotally connected thereto. The upper surfaceof the override bar 50 is contoured to provide a ramp 51, a lowersurface 52, and an upper bearing surface 53.

The bleeder apparatus of the invention operates in conjunction with aconventional bleeder valve 54 which is conventionally operated by a mainbleeder control rod 55 connected to a bleeder valve arm 56 of thebleeder valve 54. The remote bleeder operating apparatus of theinvention also includes a latch bar engaging rod 57 connected by acoupling 58 at its lower portion 59 to the main bleeder control rod 55.The upper portion of the latch bar engaging rod 57 comprises a pair ofbifurcated arms 60 connected together at their ends by a transverseengaging member 61.

Compressed air for operating the air cylinders is provided by the mainbrake air line 65 through a common supply pipe 66. A branch pipe 67feeds the primary air cylinder 36 and a branch pipe 68 feeds thesecondary air cylinder 37. The branch pipe 67 communicating with theprimary air cylinder 36 is provided with a constriction orifice 69 sodesigned that when air pressure in the main brake line 65 is reducedrapidly as in emergency braking, the air from the primary air cylinder36 is discharged more slowly than that from the secondary air cylinder37. Alternatively, the constriction 69 may be provided in the form of anadjustable valve.

The operation of the embodiment of the invention shown in FIGS. 5-7 issomewhat similar to that of the embodiment shown in FIGS. 1-4. Duringnormal braking operation, the air pressure in the main brake lineremains above 20 psi. Consequently,.the bleeder apparatus is immobile.When the train has stopped and it is desired to bleed the brakes, theengineer operates the braking control to slowly reduce the brake airline pressure to less than 20 pounds, preferably to atmosphericpressure. When the pressure reaches a value below 20 psi, the springs 45and 49 slowly move the pistons 39 and 47 toward the retracted position.As the latch bar 41 is retracted, the notch 42 of the latch bar 41engages the transverse engaging member 61 of the bleeder operating rod57, causing the bleeder valve arm 56 to be moved laterally, therebyactuating the bleeder valve 54, and bleeding the brakes. The cars may bethen disconnected and may be moved into the proper sidings without anyfurther bleeding of their brakes. When the air lines of the disconnectedcars are once again connected to the main air line of the train, the airpressure is built up to normal 75-80 psi in the main brake line, causingthe springs 45 and 49 to be compressed and the bleeder valve disengaged.In the case of an emergency braking situation or in the case of anaccident where the cars are uncoupled and the air line broken, itisnecessary that the present bleeding device be disabled and fullbraking power applied without any bleeding ofth'e brakes taking place.This is accomplished as follows. When the main air brake line issuddenly reduced to atmospheric pressure, the force of the springs 45and 49 urge the pistons 39 and 47 to retract, thereby expelling the airfrom the respective cylinders. The presence of the constriction 69causes the air to be expelled from the primary cylinder 36 more slowlythan from the secondary cylinder 37. This causes the latch bar 41 toretract slowly. The secondary cylinder does not have a constriction andconsequently the air is expelled from the cylinder rapidly. As a resultthe override bar 50 retracts rapidly. The ramp 51 engages the transverseengaging member, thereby lifting the transverse engaging member 61 outof the notch 42. As a result of this action, the bleeding device isdisabled, permitting emergency braking power to be applied to thebrakes.

The present remotely controlled bleedingsystem of the present inventionhas several advantages over conventional air braking systems. Theprimary advantage is that bleeding of all the carsmay be simultaneouslycontrolled by the engineer inthe locomotive by the simple operation ofstopping the train and then slowly placing the braking system in thefull braking condition by reducing the brake air pressure tosubstantially atmospheric. The second advantage of the present system isthat the remote bleeding function is accomplished without the loss ofthe emergency braking function. A further advantage is that the presentsystem utiizes but a few relatively inexpensive parts. An additionalimportant advantage is that the system is extremely reliable and safe touse.

While several embodiments of the invention have been shown anddescribed, other equivalent forms will now be apparent to those skilledin the art. Therefore, the embodiments shown in the drawings are merelydiagrammatic and for illustrative purposes, and are not intended tolimit the spirit and scope of the invention as above described andillustrated in the drawings. It is further to be noted that whiledirectional terms have been used, same are not to be construed as alimitation of the invention since such use has been availed of to betterdescribe the invention in the various positions shown in the drawings.

The embodiments of the invention in which an exclusive property orprivilege is claimed are defined as follows:

1. An apparatus for providing remotely controlled bleeding of the airbrakes of a railroad car having a bleeder valve and actuating meanstherefor and adapted to be operated from a common brake air line, saidapparatus comprising:

a. an air-operated cylinder comprising:

1. means defining a cylinder chamber adapted to be connected to saidbrake air line,

2. a piston slidably mounted in said chamber,

3. a piston rod affixed at one end to said piston and having a portionthereof extending out of said cylinder,

4. spring means mounted in said cylinder chamber urging said piston inthe direction for retracting said piston rod, b. latch means connectedto the outer end of saidpiston rod,

c. latch engagingmeans operatively associated with said latch means. andadapted to be engaged thereby, andadapted to be operatively connected tosaid bleeder valve actuating means, and

d. means adapted to disengage said latch engaging means from said latchmeans when said piston rod is rapidly retracted by the action of saidspring means, whereby when air pressure in'said brake air line isreduced slowly to a value permitting said piston rod to be slowlyretracted by said' spring means, said latch means engages said latchengaging means and actuates said bleeder valve thereby causing saidbrakes to be bled, and whereby when the pressure in said brake air lineis rapidly reduced to atmospheric pressure, said disengaging means (d)disengages said latch engaging means (c) from said latch means (b) andprevents actuation of said bleeder valve. r

2. An apparatus according to claim 1, wherein said latch means (b)comprises a latch .bar having a notch provided at the upper'edgethereof, and wherein said latch engaging means (c) has a transversemember adapted to be received and engaged within said notch.

3. An apparatus according to claim 2, wherein said disengaging means (d)comprises a ramp provided at the upper edge of said latch barintermediate said notch and said piston rod and ascending toward theedge of said notch, whereby when the pressure in said brake air line israpidly decreased to substantially atmospheric pressure, said transversemember rides up said ramp and clears said notch, thereby avoidingactuation of said bleeder valve.

4. An apparatus according to claim 1, wherein said air-operated cylinderand said spring means are so designed that said spring means iscompressed when an air pressure greater than about 20 psi is present insaid brake air line.

5. An apparatus according to claim 3, wherein the side wall of saidnotch adjacent said ramp is inclined, thereby permitting said transversemember to be disengaged from said notch.

6. An apparatus according to claim 2, wherein said disengaging means (d)comprises:

1. a secondary air operated cylinder connected to said brake air linehaving a cylinder chamber with a piston disposed therein, a piston rodconnected to said piston and spring mearis'urging said piston in thedirection in which said piston rod is retracted, and

2. a release bar connected to said piston rod arranged, when said pistonrod is retracted by said spring means, to lift said transverse memberout of said notch, and means provided with said firstnamed cylinder tocause the piston thereof to be retracted more slowly than that of saidsecondary cylinder, whereby when the brake air line pressure is slowlyreduced to substantially atmospheric pressure, said bleeder valve isactuated, and when said brake air line pressure is rapidly reduced tosubstantially atmospheric pressure, said secondary cylinder operatesmore rapidly than said first-named cylinder, thereby disengaging saidtransverse memfirst-named and said secondary cylinder and the springmeans therein are arranged so that said springs are compressed when theair pressure in said brake air line is at least about 20 psi.

9. An apparatus according to claim 6, wherein said release bar isprovided with a ramp adapted to lift said transverse member out of saidnotch when said release bar is retracted by retraction of the piston rodto which it is connected.

i l t t i P0405) UNETED STATES PATENT UFFKCE (5/69,) ttimmtilmstCORRECTION l etent No. w g 39" D ted August 14, 1973 Inventor(s) Qlar'k1Dm Sill It is ceztified that QITOZ." appears in the above-identifiedpatent and that said Lettezrs Patent are hereby corrected as shownbelow:

In the Abstract, Column 2 line 2, for "cars. the" read cars/J, The line13, carrect the spelling of "integral"., 7

Column 5 line 38,, correct the spelling of "utilizes".

Column 6, line 28 fer "be" read be Signed and sealed this 12th day bf'Mar chl974.

(SEAL) Attest:

EDWARD M.PLETCHER,JR. C. MARSHALL DANN Attesting Officer Commissioner ofPatents

1. An apparatus for providing remotely controlled bleeding of the airbrakes of a railroad car having a bleeder valve and actuating meanstherefor and adapted to be operated from a common brake air line, saidapparatus comprising: a. an air-operated cylinder comprising:
 1. meansdefining a cylinder chamber adapted to be connected to said brake airline,
 2. a piston slidably mounted in said chamber,
 3. a piston rodaffixed at one end to said piston and having a portion thereof extendingout of said cylinder,
 4. spring means mounted in said cylinder chamberurging said piston in the direction for retracting said piston rod, b.latch means connected to the outer end of said piston rod, c. latchengaging means operatively associated with said latch means and adaptedto be engaged thereby, and adapted to be operatively connected to saidbleeder valve actuating means, and d. means adapted to disengage saidlatch engaging means from said latch means when said piston rod israpidly retracted by the action of said spring means, whereby when airpressure in said brake air line is reduced slowly to a value permittingsaid piston rod to be slowly retracted by said spring means, said latchmeans engages said latch engaging means and actuates said bleeder valvethereby causing said brakes to be bled, and whereby when the pressure insaid brake air line is rapidly reduced to atmospheric pressure, saiddisengaging means (d) disengages said latch engaging means (c) from saidlatch means (b) and prevents actuation of said bleeder valve.
 2. apiston slidably mounted in said chamber,
 2. An apparatus according toclaim 1, wherein said latch means (b) comprises a latch bar having anotch provided at the upper edge thereof, and wherein said latchengaging means (c) has a transverse member adapted to bc received andengaged within said notch.
 2. a release bar connected to said piston rodarranged, when said piston rod is retracted by said spring means, tolift said transverse member out of said notch, and means provided withsaid first-named cylinder to cause the piston thereof to be retractedmore slowly than that of said secondary cylinder, whereby when the brakeair line pressure is slowly reduced to substantially atmosphericpressure, said bleeder valve is actuated, and when said brake air linepressure is rapidly reduced to substantially atmospheric pressure, saidsecondary cylinder operates more rapidly than said first-named cylinder,thereby disengaging said transverse member from said notch andpreventing actuation of said bleeder valve.
 3. a piston rod affixed atone end to said piston and having a portion thereof extending out ofsaid cylinder,
 3. An apparatus according to claim 2, wherein saiddisengaging means (d) comprises a ramp provideD at the upper edge ofsaid latch bar intermediate said notch and said piston rod and ascendingtoward the edge of said notch, whereby when the pressure in said brakeair line is rapidly decreased to substantially atmospheric pressure,said transverse member rides up said ramp and clears said notch, therebyavoiding actuation of said bleeder valve.
 4. An apparatus according toclaim 1, wherein said air-operated cylinder and said spring means are sodesigned that said spring means is compressed when an air pressuregreater than about 20 psi is present in said brake air line.
 4. springmeans mounted in said cylinder chamber urging said piston in thedirection for retracting said piston rod, b. latch means connected tothe outer end of said piston rod, c. latch engaging means operativelyassociated with said latch means and adapted to be engaged thereby, andadapted to be operatively connected to said bleeder valve actuatingmeans, and d. means adapted to disengage said latch engaging means fromsaid latch means when said piston rod is rapidly retracted by the actionof said spring means, whereby when air pressure in said brake air lineis reduced slowly to a value permitting said piston rod to be slowlyretracted by said spring means, said latch means engages said latchengaging means and actuates said bleeder valve thereby causing saidbrakes to be bled, and whereby when the pressure in said brake air lineis rapidly reduced to atmospheric pressure, said disengaging means (d)disengages said latch engaging means (c) from said latch means (b) andprevents actuation of said bleeder valve.
 5. An apparatus according toclaim 3, wherein the side wall of said notch adjacent said ramp isinclined, thereby permitting said transverse member to be disengagedfrom said notch.
 6. An apparatus according to claim 2, wherein saiddisengaging means (d) comprises:
 7. An apparatus according to claim 6,wherein said means for causing said first named cylinder to retract moreslowly by the action of said spring means comprises an air supply pipeconnected thereto having an inner bore with at least a portion thereofconstricted to a smaller diameter than that of the air supply pipe tosaid secondary cylinder.
 8. An apparatus according to claim 6, whereinsaid first-named and said secondary cylinder and the spring meanstherein are arranged so that said springs are compressed when the airpressure in said brake air line is at least about 20 psi.
 9. Anapparatus according to claim 6, wherein said release bar is providedwith a ramp adapted to lift said transverse member out of said notchwhen said release bar is retracted by retraction of the piston rod towhich it is connected.